Fireproof construction



March 14, 1939. c. R. WILLIAMS FIREPROOF CONSTRUCTION Filed July 19, 1937 2 Sheets-Sheet 1 Patented Mar. 14, 1939 l 29159974 UNITED sTATEs PATENT OFFICE FIR'EPROOF CONSTRUCTION Charley R. Williams, Chicago, Ill. Application July 19, 1937, Serial N0. 154,475

' 1a claims. (o1. 10s- 23) This invention relates to a flreproof-or fire straight, longitudinal members 3 between the resistant structural member and the process of ends of which a spacing and strengthening memproducing it. ber 4 is positioned. A U-shaped end plate 5 may It has for one object to provide a structural be applied to each end and where applied covers 5 member or unit which is formed of a normally the end and a portion of the side members 3, as combustible material but has associated with it, shown at the right of Figure 2. Bolts 6 or other so as to form part of the unit, a fire resistant suitable attaching means secure the ends of the exterior portion which may be in the form of a truss members together and hold the plate 5 in sheathing or covering. place when the latter is used. In the case of a ',j Another object is to provide a method of formlarge truss, the straight members 3 will not run 1 .ing the said structural member. Another obfrom end to end of the truss and reinforcing and ject is to provide a re resistant sheathing or joining members 1 are used to effect a joint behousing which may be applied to an otherwise tween ends of the members 3. Such adjoining complete structural member either before that members are secured together by bolts 8 and by 15 member is used in ra building or after it has been any other suitable attaching means. The sec- L),

so used. tion of Figure 5 is taken at such a joint. v Other objects will appear from time to time A generally curved top is formed for the truss in the specication and claims. and is made up of members 9, 9, which at their 'Ihe invention is illustrated more or less diaends are secured to the members 3 and may be 2o grammatically in the accompanying drawings, embraced and engaged by the plates 5. A plu- 20 wherein: rality of diagonal bracing members l0 may be Figure 1 is a vertical section through a building installed and these are preferably positioned so in which the present invention is applied to a that their lower ends lie between the members 3 roof supporting truss; and their upper ends between the members 9.

25 Figure 2 is a fragmentary horizontal sectional Such diagonal members are shown generally in 2.5 detail on an enlarged scale, taken at line 2-2 Figure 1 and adjacent their lower ends in section of Figure 1; in Figure 2 and adjacent their upper ends in Figure 3 is a perspective View of the bottom perspective in Figure 7. Vertical members Il portion of the sheathing with parts in section; may also be applied and connected top and bot- Figure 4 is a side elevation in perspective show-y tom to the upper and lower truss members. At :fc ing another part of the sheathing; the point of attachment of these members to the Figure 5 is a transverse vertical section taken top or bottom units of the truss, bolts i2 or other on an enlarged scale at line 5--5 of Figure 1; fastening means may be used to hold the parts Figure 6 is a vertical sectional detail taken at in place. line 6-6 of Figure 2 on an enlarged scale; While the .particular form of truss Shown has 35 Figure 7 is a perspective showing a portion of been described in some detail, the invention is the roof of Figure 1' with parts broken away, notlimited to this truss and many other forms parts omitted and parts in section on a scale of truss detail and construction may be used enlarged with respect to that used in Figure 1. where the housing or sheathing of the present o Like parts are designated by like characters invention is to be applied and the details ofthe 40.

throughout the specification and drawings. form thus shown have been described to illus- The invention is shown as applied to a roof trate the interrelation between the truss generally truss supporting the roof oi a building. Side and the sheathing which forms the more parwalls I of the building are shown supporting the ticular subject of the invention.

L15 truss. Internal walls or supporting members 2 As shown, roof beams I3 rest upon and are 45 may be used and upon them the truss is supsupported by the trusses and upon them are ported. The invention may be applied to many positioned and supported roof planks or other other forms of structural members besides trusses covering members I4.

and is not limited to theL particular application Where the structure of the present invention ."1 shown nor to the particular truss form shown is to be applied to a truss of the type shown, it

nor to the means of supporting the truss, alis preferable to providein addition to the truss though one of the more important uses of the spacing and attaching members of such size and invention is that shown in which a wooden truss thickness that the fire resistant sheathing may is rendered re resistant or fire proof.v be applied without serious bending or distortion.

As shown, the truss comprises a plurality of For this purpose preferably vertical spacers l5 o are secured by nailing or otherwise to the exterior of the truss. As shown particularly in Figures 5 and 7, these spacers need not extend to the top of the truss and normally a space I6 is left between the top of each spacer and the top of the truss or the bottom of the roof beam I3.

Since it is desirable to have a 'lre resistant sheathing or covering extending clear to the ceiling, that is to say, above the top of the truss proper, spacing and attaching cleats i'I may be secured to the roof beams I3, as shown in detail in Figures 5 and 7. To these are secured members I8 which are formed of heat resistant or re proof material. As shown in the detailed sectional view of Figure 5, two such members are applied between each pair of roof beams I3 and define the two sides of the composite truss and nre resistant construction member. These members I8 extend downwardly toward the top of a spacer I5 and into the space I 6 which is left between the top of the member I5 and the lower edge of the roof beam I3. These members I8 are preferably fastened in place by nails or screws I9 which are normally madeof copper or other corrosion-resistant material.

Secured to the spacers I5 by nails or other fasteners 2E), also preferably of corrosion-resistant material such as copper, are the side sheathing members 2|. These extend normally from the lower edges of the roof beams I3 to the bottom of the truss and thus furnish complete enclosure and sheathing for both sides of the truss. As shown particularly in Figure 5, the upper edges of the members 2| overlap with the lower edges of the members I8 and thus prevent the occurrance of any gap between the two through which re or heat might readily penetrate.

Spacers 22 are provided for the bottom of the truss and as shown in Figures 5 and 6, may be secured to the truss by fastening means such as nails or screws 23, preferably of corrosion-resistant material such as copper, and below these one or more sheets or strips of fire resistant material 24 are positioned. These strips of material may be secured to the spacers 22 in any desired manner or may be mounted in the bottom of a trough-like member 25 which has upturned side flanges 26 perforated as at 2'I to receive nails or screws or other fastening members 28. For some purposes it is not necessary to secure the spacers directly to the bottom of the truss but they and the strip 24 may be mounted in or secured to, or supported by the trough 25. After these spacers and the strip 2li are mounted they are within or are enclosed or surrounded by the trough 25 and the sides or flanges 26 of the trough overlie the lower edges of the sheathing members 2I, thus closing the bottom of the sheathing structure and surrounding it on its lower edge in addition to the heat resistant member 24, with a metal strengthening and reinforcing unit which serves not merely to enclose the parts but to hold them together.

The construction shown in the drawings and described above provides about the truss or other structural member to which the sheathing may be applied a fire resistant sheathing which completely encloses the truss or equivalent member and is preferably spaced away from the structural members of the truss. Thus not only is the iire resistant housingV provided which 4directly holds heat and re away from the structural members, but this housing is itself spaced away from them so that an air space is provided with- A in the total housing and between the members which make up the housing and the truss itself, which serv-es as a further iireproofing or re resistant feature.

Where the truss is to be made up as a unit before installation, they nre resistant enclosure of the present invention may be applied to the truss 'before it is built intoy a building or if it is desir-ed to build the truss into the building first, that may be done and the re resistant covering applied thereafter to the truss lwhile it is in place in the building. Thus it is useful both for new and for old constructions. Although the invention is shown as applied to a wooden and, therefore, inflammable truss, it might be used for the protection of metal or other relatively noninflammable truss-es or building units. The greatest need, however, occurs in connection with wooden trusses and hence, although the invention is not limited to that use, it is shown in that connection.

It will be realized that whereas I have herewith shown and described a practical operative device, nevertheless many changes might be made in the size, shape, number and disposition of the parts without departing from the spirit of the invention and I wish, therefore, that my showing be taken as in a sense diagrammatic.

In particular the side sheathing members might be of almost any desired shape to lit the structural member or unit to which they are applied and instead of having separate members spaced between the roof beams or rafters, the side sheathing member might be made to fit the con- Y tour of the roof and notched or shaped to embrace or t around the roof beams. It is ordinarily simpler to have the separate members for filling in the spaces between the roof beams, but it is within the contemplation of the invention to use either or both constructions.

The iire resistant covering o-f the present invention is arranged to be light so that it adds only very slightly to the total weight o-f the truss and the vertical spacers being secured as they are to the top and bottom members of the truss, further stiffen and strengthen it with the result that the added strengthening to the truss as as whole, because of the association with it of the i'lre resistant sheathing, more than compensates for the slight addition in weight and in no way detracts from the light weight-and other advantages of wooden trusses and particularly trusses of the bowstring type, which is the type here illustrated, although the invention is in no sense limited to such trusses.

The covering maybe of any desired material and may be painted any desirable color, or may have applied to it a coating of further insulating or fire resisting material such as asbestos or anything else desired. vThe use of a light colored paint, whether it be reproof or not, has the advantage of creating a light reflecting surface, where this may be necessary, as in factories and industrial buildings of many sorts particularly and, of course, adds this reflecting surface where in the ordinary bowstring or open truss there is no reflecting surface.

The most important advantage of the covering is, of course, that of preventing, retarding and conning the spread of fire. In the case of trusses of the general type shown as now constructed, fire readily spreads from one end of the building to the other through the latticework formed bythe trusses. This latticework being formed of wood, readily ignites and adds fuel to the nre with the result that in practice in a large percentage of res occurring in buildings where' the roof is supported by wooden trusses, the fire spreads readily and the roof trusses burn quickly and weaken to`v the' point where the entire roof falls with resultant serious damage to the` side walls which are frequently pushed outward when the arc of the' truss in falling creates pressure at the ends, and serious damage results also tothe contents of the building because the falling of the roof not merely tends to crush or destroy the contents but also adds fuel to the fire yalready burning in the building. The provision of the re resistant coating or sheathing about the truss insulates it from the heat of the fire so that the truss members themselves are less likely to bec'ome heated to the pointV of combustion, and also furnishes a mechanical shield from the ames should they come high enough otherwise to contact the truss members and since the spaces otherwise left open in a truss of the type shown are completely closed in bythe sheathing members, the sweep of re along the roof of the building is resisted and the enclosed trusses thus form in effect a series of fire walls, depending from the roof. These so-called re walls coni-lne superheated air vrising from a flame within the building and not merely prevent the spread of flames but p-revent the spread and movement of this superheated air and conne and isolate it and this occurs even though the roof beams or planks should burn because in this confined zone they burn out and permit the escape of the superheated air, and when this occurs the damage can be reduced and restricted as compared to that which occurs under present conditions with open wooden trusses since the tendency of the heat or flames or both to spread from end to end of the building, igniting the entire roof as they travel along, is greatly resisted or entirely prevented, and even though the heat be suiicient under normal conditions to ignite such a truss, experience has shown that with the construction of the present invention Very considerable charring of the covering material may occur without any ignition or charring of the truss members themselves and without any reduction in their strength, and the cost of replacing the fire resistant coating is infinitely less than that of replacing a truss or a part of the roof.

The invention therefore contemplates not merely the production of a fire resistant structural member, but the association in a building of a plurality of such members to form in effect first, relatively fireproof trusses or structural members, and, second, a plurality of fire walls which serve to prevent spread of heat and ames, serve to isolate heat and flames, and consequently to isolate the total resultant damage.

The device illustrated may be used without complete coverage of the sides of the truss. For example, the trough-like construction of Figure 3 may be used alone or it may be used with side portions which extend only partly upward along the sides of the truss. So long as the bottom member of the truss remains intact, the danger of collapse of the roof is greatly reduced and the use of the member of Figure 3 with or without partial side shielding is, therefore, useful. The device shown in Figure 3 may be made up rin regular lengths and applied to trusses already in position or to trusses at the time of manufacture and while not giving them full fire resistant protection, nonetheless gives important fire resistance to that portion of the trusses which it is most necessary to preserve.

I claim:

l. In combination, a load carrying'roof truss 2. In combination, a load carrying roof truss;

and means for rendering it fire resistant, said means comprising an enclosure of lire resistant material for the sides andV bottom of said truss, including side sheets of re' resistant material and separate sheets of re resistant material positioned partially above said side sheets with their lower edges overlapping the upper edges of said side sheets and positioned inside of said side sheets, and a trough-like member covering the bottom of the truss and engaging and covering the bottom edges of the side sheets.

3. In combination, a load carrying roof truss and means for rendering it re resistant, said means comprising an enclosure of fire resistant material for the sides and bottom of said truss, including side sheets of fire resistant material, a sheet of re resistant material positioned along the bottom of said truss, and a trough-like member covering the bottom of the truss and engaging and covering the bottom edges of the side sheets :f

and said bottom sheathing member.

4. In combination, a load carrying roof truss and means for rendering it fire resistant, said means comprising an enclosure of re resistant material for the sides and bottom of said truss, including sidesheets of re resistant material and separate sheets of fire resistant material positioned partially above said side sheets with their lower edges overlapping the upper edges of said side sheets and positioned inside of said side sheets, a sheet of fire resistant material positioned along the bottom of said truss, and a trough-like member covering the bottom of the truss and engaging and covering the bottom edges of the side sheets and said bottom sheathing member.

5. In combination with a truss having top: and bottom members, a re resistant enclosure therefor, comprising spacing members secured to said truss, side sheathing members of lire resistant material secured to said spacing members, a bottom sheathing member for the bottom of said truss, spacers interposed between said bottom sheathing member and said truss, a metallic trough-like member having upwardly extending anges positioned along the. bottom of said truss, enclosing said bottom sheathing member and said bottom spacers and extending upwardly beyond the bottom edges of said side sheathing members.

6. In combination with a truss, a fire resistant enclosure therefor comprising side and bottom sheathing members of re resistant material positioned about said truss, and spacers secured to said truss between it andthe sai-d sheathing members, and an additional bottom enclosing member formed of metal and pro-vided with side flanges, said last mentioned enclosing member overlying said bottom sheathing member and the lower edges of said side sheathing members.

7. In combination, a load carrying roof truss and means for rendering it fire resistant, said means comprising van enclosure of fire resistant material for the sides and bottom of said truss, including side sheets of fire resistant material and a member covering the bottom of the truss and engaging the side sheets.

8. In combination, a load carrying roof truss and means for rendering it re resistant, said means comprising an enclosure of re resistant material for the sides and bottom of said truss, including side sheets of fire resistant material, a sheet of re resistant material positioned along the bottom of said truss, and a member covering the bottom of the truss and engaging the side sheets and said bottom sheathing member.

9. In combination a load carrying roof truss comprising upper and lower members and means for rendering it re resistant, said means comprising an enclosure of re resistant material for the sides and bottom of said truss including a part extending along the bottom of said truss, parts extending along the sides of said truss and extending upwardly beyond the upper edge of each member of said truss.

10. In combination, a load carrying roof truss comprising upper and lower members and means for rendering it fire resistant, said means comprsing an enclosure of fire resistant material for the sides and bottom of said truss including a part extending along the bottom of said truss, parts extending along the sides of said truss and extending upwardly beyond the upper edge of each member of said truss, said upwardly extending parts being indented along their upper edge to inter-lt with structural members with which the truss is adapted to cooperate.

11. In combination, a load carrying roof truss and means for rendering it lire resistant, said truss comprising a longitudinal bottom member and other structural members above said bottom member, said means comprising an enclosure of lre resisting material for said longitudinal bottom member, which enclosure includesl parts underlying the bottom of said longitudinal member and parts extending, upwardly along the side of said longitudinal mcmber and comprises a trough-like structure formed of ire resisting material and underlying the bottom'of the truss and extending upwardly along the sides of the truss, said trough-like structure including insulation and a metallic memberrand means for spacing the metallic member from the truss, the metallic member being positioned outwardly with respect to the insulation.

12, A fire resistant composite member adapted to be secured to a part to be insulated and comprising a trough-like metallic part having upwardly extending anges shaped for attachment to said part to be insulated, and a body of insulating material surrounded in part by said trough-like member and Yadapted to hold the trough-like member out of contact with said part to be insulated.

13. A nre resistant composite member adapted -to be secured to a part to be insulated and cornprising a trough-like metallic part having upwardly extending flanges shaped for attachment' to said part to be insulated, and a body of insu.- lating material surrounded in part by said trough-like member and adapted to hold the trough-like member out of contact with said part to be insulated, and additional spacers positioned Within the trough.

CHARLEY R. WILLIAMS. 

